Hereditary Nigremia and Hemoglobin MIwate

Abstract

Hb MIwate is a new abnormal hemoglobin that had never been recorded prior to 1960. It is the cause of cyanosis in the congenital nigremia which is inherited as an autosomal dominant character. The disease may be considered on the basis of the chemical study described above as follows:-The nigremia is a hemoglobinopathy due to a mutation that has caused substitution by tyrosine for the histidine of the 87th amino acid residue. The patient of this disease is the heterozygote to be designated by the genetic formula (αMI/αΛ, βΛ/βΛ): the homozygote (αMI/αMI, βΛ/βΛ) has not yet been discovered. Possibly, this combination will act as a lethal on the fetus on account of deficient oxygenation of the fetal circulation.